Astronomy:NGC 2867

From HandWiki
Short description: Planetary nebula in the constellation Carina
NGC 2867
Emission nebula
Planetary nebula
NGC 2867.jpg
Hubble Space Telescope (HST) image of NGC 2867
Credit: HST/NASA/ESA
Observation data: J2000 epoch
Right ascension 09h 21m 25.38336s[1]
Declination−58° 18′ 40.6167″[1]
Distance7,270 ly (2,228 pc)[2] ly
Apparent magnitude (V)9.7[3]
Apparent dimensions (V)12″[4]
43.3″ × 35.6″[5]
ConstellationCarina
DesignationsESO 126-8, PN G278.1-05.9,[6] Caldwell 90
See also: Lists of nebulae

NGC 2867 (also known as Caldwell 90) is an elliptical[5] Type II[7] planetary nebula in the southern constellation of Carina, just over a degree to the NNW of the star Iota Carinae.[8] It was discovered by John Herschel on April 1, 1834. Herschel initially thought he might have found a new planet, but on the following night he checked again and discovered it had not moved.[3] The nebula is located at a distance of 7,270 light-years from the Sun.[2]

The central star of the nebula is of spectral type WC3[9] and is in the process of evolving into a white dwarf, having previously shed the atmosphere that created the surrounding nebula. It is now a hydrogen deficient GW Vir variable that is undergoing non-radial pulsations with an amplitude of less than 0.3 in magnitude. The star has an estimated temperature of 165+18
−20
 kK
with 5% of the radius of the Sun and is radiating 1,400 times the Sun's luminosity.[5]

The surrounding nebula is fairly typical but does shows carbon enrichment, which suggests the progenitor star was not massive but did pass through third dredge-up. The category of central star has excited a very high degree of ionization in the nebula.[7] The shape of the nebula appears somewhat elongated, which may indicate an interaction with the surrounding interstellar matter. The nebula halo may be a recombination of two separate halos, which could indicate a peculiar mass-loss history.[10]

References

  1. 1.0 1.1 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode2018A&A...616A...1G.  Gaia DR2 record for this source at VizieR.
  2. 2.0 2.1 Stanghellini, Letizia et al. (December 10, 2008). "The Magellanic Cloud Calibration of the Galactic Planetary Nebula Distance Scale". The Astrophysical Journal 689 (1): 194–202. doi:10.1086/592395. Bibcode2008ApJ...689..194S. 
  3. 3.0 3.1 O'Meara, Stephen James (2016). Deep-Sky Companions: The Caldwell Objects. Cambridge University Press. p. 415. ISBN 9781107083974. https://books.google.com/books?id=MMfxDAAAQBAJ&pg=PA415. 
  4. "SEDS Online NGC Catalogue". Results for NGC 2867. http://spider.seds.org/ngc/ngc.cgi?2867. 
  5. 5.0 5.1 5.2 Keller, Graziela R. et al. (August 2014). "UV spectral analysis of very hot H-deficient [WCE]-type central stars of planetary nebulae: NGC 2867, NGC 5189, NGC 6905, Pb 6 and Sand 3". Monthly Notices of the Royal Astronomical Society 442 (2): 1379–1395. doi:10.1093/mnras/stu878. Bibcode2014MNRAS.442.1379K. 
  6. "NGC 2867". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=NGC+2867. 
  7. 7.0 7.1 Aguilar, A.; Carramiñana, A., eds (July 2001). "Planetary Nebulae with [WR] nuclei". IX Latin American Regional IAU Meeting, "Focal Points in Latin American Astronomy", held in Tonantzintla, Mexico, Nov 9-13, 1998. 61. Bibcode2001RMxAC..11...61P. 
  8. Sinnott, Roger W.; Perryman, Michael A. C. (1997). Millennium Star Atlas. 2. Sky Publishing Corporation and the European Space Agency. p. 994. ISBN 0-933346-83-2. 
  9. Werner, K. et al. (June 1992). "A spectacular mass-loss event of the central star of Longmore 4.". Astronomy and Astrophysics 259: L69–L72. Bibcode1992A&A...259L..69W. 
  10. Corradi, R. L. M. (2003). "Observations of Planetary Nebulae Haloes". in Kwok, Sun; Dopita, Michael; Sutherland, Ralph. Planetary Nebulae: Their Evolution and Role in the Universe, Proceedings of the 209th Symposium of the International Astronomical Union held at Canberra, Australia, 19-23 November, 2001. Astronomical Society of the Pacific. p. 447. Bibcode2003IAUS..209..447C. 

External links